Early diagnosis is a prerequisite of the more successful treatment of cancer. In gynaecological cancers, such as ovarian, endometrial and cervical cancers, the recent efforts are aimed at finding novel diagnostic biomarkers to help reduce the worldwide health burden associated with these cancers. In this review, we focus on the recent research progress in circulating, particularly cell-free microRNAs expression achieved in ovarian, endometrial and cervical cancers showing an opportunity to find novel diagnostic biomarkers for these malignant diseases. With the onset of microRNAs investigations showing their diagnostic potential in many diseases, their role in gynaecological cancers has been examined as well. However, similarly as in many other diseases, the vast majority of research on microRNAs expression has been dealing with tissue samples and cell lines. Recently, as the novel approaches focused on cell-free microRNAs expression have emerged, several studies identified their potential diagnostic and prognostic value in gynaecological cancers using blood, serum/plasma or urine samples. More research will be needed to establish circulating and extracellular microRNAs as the novel diagnostic markers for gynaecological malignancies. Inconsistency of results across the studies due to technical and biological variation, and a low number of this kind of investigations are the main potential pitfalls remaining to be resolved.